Leaders of Mercury Computer Systems Inc. in Chelmsford, Mass., are providing another 23 multicomputer systems from their RACE line for deployment aboard the U.S. Army`s Predator medium-altitude endurance unmanned aerial vehicle (UAV). The job is part of a $3.9 million subcontract from Northrop Grumman Electronic Sensors and Systems Division in Baltimore. Northrop Grumman engineers will integrate the computers in their Tactical Endurance Synthetic Aperture Radar (TESAR) system, which works with an associated ground station to produce photo-quality radar imagery with 1-foot resolution. The RACE computers process the radar signals for downlinking to the ground station. - J.R.